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Garate Z, Quintana-Bustamante O, Crane AM, Olivier E, Poirot L, Galetto R, Kosinski P, Hill C, Kung C, Agirre X, Orman I, Cerrato L, Alberquilla O, Rodriguez-Fornes F, Fusaki N, Garcia-Sanchez F, Maia TM, Ribeiro ML, Sevilla J, Prosper F, Jin S, Mountford J, Guenechea G, Gouble A, Bueren JA, Davis BR, Segovia JC. Generation of a High Number of Healthy Erythroid Cells from Gene-Edited Pyruvate Kinase Deficiency Patient-Specific Induced Pluripotent Stem Cells. Stem Cell Reports 2015; 5:1053-1066. [PMID: 26549847 PMCID: PMC4682065 DOI: 10.1016/j.stemcr.2015.10.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 10/02/2015] [Accepted: 10/05/2015] [Indexed: 01/30/2023] Open
Abstract
Pyruvate kinase deficiency (PKD) is a rare erythroid metabolic disease caused by mutations in the PKLR gene. Erythrocytes from PKD patients show an energetic imbalance causing chronic non-spherocytic hemolytic anemia, as pyruvate kinase defects impair ATP production in erythrocytes. We generated PKD induced pluripotent stem cells (PKDiPSCs) from peripheral blood mononuclear cells (PB-MNCs) of PKD patients by non-integrative Sendai viral vectors. PKDiPSCs were gene edited to integrate a partial codon-optimized R-type pyruvate kinase cDNA in the second intron of the PKLR gene by TALEN-mediated homologous recombination (HR). Notably, we found allele specificity of HR led by the presence of a single-nucleotide polymorphism. High numbers of erythroid cells derived from gene-edited PKDiPSCs showed correction of the energetic imbalance, providing an approach to correct metabolic erythroid diseases and demonstrating the practicality of this approach to generate the large cell numbers required for comprehensive biochemical and metabolic erythroid analyses. Patient-specific PKDiPSCs are generated from PB-MNCs by a non-integrative system PKDiPSCs are gene edited to insert a partial co-RPK in the PKLR locus mediated by TALEN An SNP in the homology arm leads to allele-specific homologous recombination Gene-edited PKDiPSCs generate a high number of metabolically corrected erythroid cells
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102
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Lohmann F, Dangeti M, Soni S, Chen X, Planutis A, Baron MH, Choi K, Bieker JJ. The DEK Oncoprotein Is a Critical Component of the EKLF/KLF1 Enhancer in Erythroid Cells. Mol Cell Biol 2015; 35:3726-38. [PMID: 26303528 PMCID: PMC4589598 DOI: 10.1128/mcb.00382-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 05/06/2015] [Accepted: 08/17/2015] [Indexed: 02/07/2023] Open
Abstract
Understanding how transcriptional regulators are themselves controlled is important in attaining a complete picture of the intracellular effects that follow signaling cascades during early development and cell-restricted differentiation. We have addressed this issue by focusing on the regulation of EKLF/KLF1, a zinc finger transcription factor that plays a necessary role in the global regulation of erythroid gene expression. Using biochemical affinity purification, we have identified the DEK oncoprotein as a critical factor that interacts with an essential upstream enhancer element of the EKLF promoter and exerts a positive effect on EKLF levels. This element also binds a core set of erythroid transcription factors, suggesting that DEK is part of a tissue-restricted enhanceosome that contains BMP4-dependent and -independent components. Together with local enrichment of properly coded histones and an open chromatin domain, optimal transcriptional activation of the EKLF locus can be established.
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103
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Amanatiadou EP, Papadopoulos GL, Strouboulis J, Vizirianakis IS. GATA1 and PU.1 Bind to Ribosomal Protein Genes in Erythroid Cells: Implications for Ribosomopathies. PLoS One 2015; 10:e0140077. [PMID: 26447946 PMCID: PMC4598024 DOI: 10.1371/journal.pone.0140077] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 09/21/2015] [Indexed: 12/15/2022] Open
Abstract
The clear connection between ribosome biogenesis dysfunction and specific hematopoiesis-related disorders prompted us to examine the role of critical lineage-specific transcription factors in the transcriptional regulation of ribosomal protein (RP) genes during terminal erythroid differentiation. By applying EMSA and ChIP methodologies in mouse erythroleukemia cells we show that GATA1 and PU.1 bind in vitro and in vivo the proximal promoter region of the RPS19 gene which is frequently mutated in Diamond-Blackfan Anemia. Moreover, ChIPseq data analysis also demonstrates that several RP genes are enriched as potential GATA1 and PU.1 gene targets in mouse and human erythroid cells, with GATA1 binding showing an association with higher ribosomal protein gene expression levels during terminal erythroid differentiation in human and mouse. Our results suggest that RP gene expression and hence balanced ribosome biosynthesis may be specifically and selectively regulated by lineage specific transcription factors during hematopoiesis, a finding which may be clinically relevant to ribosomopathies.
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104
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Sakamoto S, Kawabata H, Masuda T, Uchiyama T, Mizumoto C, Ohmori K, Koeffler HP, Kadowaki N, Takaori-Kondo A. H-Ferritin Is Preferentially Incorporated by Human Erythroid Cells through Transferrin Receptor 1 in a Threshold-Dependent Manner. PLoS One 2015; 10:e0139915. [PMID: 26441243 PMCID: PMC4595017 DOI: 10.1371/journal.pone.0139915] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 09/19/2015] [Indexed: 02/04/2023] Open
Abstract
Ferritin is an iron-storage protein composed of different ratios of 24 light (L) and heavy (H) subunits. The serum level of ferritin is a clinical marker of the body's iron level. Transferrin receptor (TFR)1 is the receptor not only for transferrin but also for H-ferritin, but how it binds two different ligands and the blood cell types that preferentially incorporate H-ferritin remain unknown. To address these questions, we investigated hematopoietic cell-specific ferritin uptake by flow cytometry. Alexa Fluor 488-labeled H-ferritin was preferentially incorporated by erythroid cells among various hematopoietic cell lines examined, and was almost exclusively incorporated by bone marrow erythroblasts among human primary hematopoietic cells of various lineages. H-ferritin uptake by erythroid cells was strongly inhibited by unlabeled H-ferritin but was only partially inhibited by a large excess of holo-transferrin. On the other hand, internalization of labeled holo-transferrin by these cells was not inhibited by H-ferritin. Chinese hamster ovary cells lacking functional endogenous TFR1 but expressing human TFR1 with a mutated RGD sequence, which is required for transferrin binding, efficiently incorporated H-ferritin, indicating that TFR1 has distinct binding sites for H-ferritin and holo-transferrin. H-ferritin uptake by these cells required a threshold level of cell surface TFR1 expression, whereas there was no threshold for holo-transferrin uptake. The requirement for a threshold level of TFR1 expression can explain why among primary human hematopoietic cells, only erythroblasts efficiently take up H-ferritin.
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105
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Golov AK, Gavrilov AA, Razin SV. The Role of Crowding Forces in Juxtaposing β-Globin Gene Domain Remote Regulatory Elements in Mouse Erythroid Cells. PLoS One 2015; 10:e0139855. [PMID: 26436546 PMCID: PMC4593578 DOI: 10.1371/journal.pone.0139855] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 09/11/2015] [Indexed: 01/03/2023] Open
Abstract
The extremely high concentration of macromolecules in a eukaryotic cell nucleus indicates that the nucleoplasm is a crowded macromolecular solution in which large objects tend to gather together due to crowding forces. It has been shown experimentally that crowding forces support the integrity of various nuclear compartments. However, little is known about their role in control of chromatin dynamics in vivo. Here, we experimentally addressed the possible role of crowding forces in spatial organization of the eukaryotic genome. Using the mouse β-globin domain as a model, we demonstrated that spatial juxtaposition of the remote regulatory elements of this domain in globin-expressing cells may be lost and restored by manipulation of the level of macromolecular crowding. In addition to proving the role of crowding forces in shaping interphase chromatin, our results suggest that the folding of the chromatin fiber is a major determinant in juxtaposing remote genomic elements.
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106
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Lovrić E, Pavlov KH, Korać P, Dominis M. FOXP1 Expression in Normal and Neoplastic Erythroid and Myeloid Cells. COLLEGIUM ANTROPOLOGICUM 2015; 39:755-759. [PMID: 26898077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
FOXP1 protein was firstly analyzed in normal tissues, and afterwards in different tumor tissues, mainly carcinoma and lymphoma. In B-cell malignancies, its role was well explored; its expression was shown to be connected with disease prognosis in certain B-non Hodgkin lymphomas. In this study, 16 bone marrow trephine samples from patients with no hematopoietic malignancies and 10 samples from peripheral blood of healthy individuals were immunostained with anti-FOXP1 antibody. Positive cells in bone marrows were not only lymphocytes, but also cells that are immunohistochemically positive for glycophorin C or myeloperoxidase. Peripheral blood samples showed no other positive cells, but small round lymphocytes. Additionally 60 samples from patients with myeloid lineage neoplasms were analyzed. 25 samples from patients with myelodysplastic syndrome (MDS) and 35 patients with myeloproliferative disease (MPD) were double immunostained with anti-FOXP1/anti-glycophorin C and anti-FOXP1/anti-myeloperoxidase antibodies. FOXP1 was found to be expressed in 22 cases of MDS and in none of MPD cases. Its expression in MDS was observed mostly in myeloperoxidase positive cells in contrast to gylcophorin C positive cells. Only two cases revealed both myeloperoxidase positive cells and gylcophorin C positive cells expressing FOXP1 transcription factor. Our results show that FOXP1 is present in normal cells of erythroid and myeloid linages and thus suggest its possible role in development of all hematopoetic cells as well as possible involvement in neoplasm development of myeloid disorders.
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107
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Wang C, Wu X, Shen F, Li Y, Zhang Y, Yu D. Shlnc-EC6 regulates murine erythroid enucleation by Rac1-PIP5K pathway. Dev Growth Differ 2015; 57:466-473. [PMID: 26098172 DOI: 10.1111/dgd.12225] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 04/15/2015] [Accepted: 05/03/2015] [Indexed: 12/20/2022]
Abstract
Long noncoding RNAs (LncRNAs) are longer than 200 nucleotide noncoding RNAs without apparent functional coding capacity that function as regulators of cell growth and development. In recent years, increasing evidence implicates the involvement of LncRNAs in erythropoiesis. shlnc-EC6 is a LncRNA associated with erythroid differentiation but the mechanism remains undefined. In this study, we found that knockdown of shlnc-EC6 in purified mouse fetal liver erythroid progenitor and hematopoietic stem cells (FLEPHSCs) significantly blocked erythroid enucleation. We also showed that Rac1 was negatively regulated by shlnc-EC6 at the posttranscriptional level via specific binding to sites within the 3'UTR of Rac1 mRNA. Moreover, we found that knockdown of shlnc-EC6 led to upregulation of Rac1, followed by the activation of the downstream protein PIP5K, and subsequently resulted in the inhibition of enucleation in cultured mouse fetal erythroblasts. Thus, our findings suggest that shlnc-EC6 acts as a novel modulator to regulate mouse erythropoiesis via Rac1/PIP5K signaling pathway.
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108
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Ng AP, Hu Y, Metcalf D, Hyland CD, Ierino H, Phipson B, Wu D, Baldwin TM, Kauppi M, Kiu H, Di Rago L, Hilton DJ, Smyth GK, Alexander WS. Early lineage priming by trisomy of Erg leads to myeloproliferation in a Down syndrome model. PLoS Genet 2015; 11:e1005211. [PMID: 25973911 PMCID: PMC4431731 DOI: 10.1371/journal.pgen.1005211] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 04/13/2015] [Indexed: 12/12/2022] Open
Abstract
Down syndrome (DS), with trisomy of chromosome 21 (HSA21), is the commonest human aneuploidy. Pre-leukemic myeloproliferative changes in DS foetal livers precede the acquisition of GATA1 mutations, transient myeloproliferative disorder (DS-TMD) and acute megakaryocytic leukemia (DS-AMKL). Trisomy of the Erg gene is required for myeloproliferation in the Ts(1716)65Dn DS mouse model. We demonstrate here that genetic changes specifically attributable to trisomy of Erg lead to lineage priming of primitive and early multipotential progenitor cells in Ts(1716)65Dn mice, excess megakaryocyte-erythroid progenitors, and malignant myeloproliferation. Gene expression changes dependent on trisomy of Erg in Ts(1716)65Dn multilineage progenitor cells were correlated with those associated with trisomy of HSA21 in human DS hematopoietic stem and primitive progenitor cells. These data suggest a role for ERG as a regulator of hematopoietic lineage potential, and that trisomy of ERG in the context of DS foetal liver hemopoiesis drives the pre-leukemic changes that predispose to subsequent DS-TMD and DS-AMKL. An excess number of genes in trisomy on human chromosome 21 leads to the development of specific diseases in human Down syndrome. An excess copy of the gene, ERG, an ETS family transcription factor, has been implicated in abnormal blood system development in Down syndrome. In this study we show how trisomy of Erg in a murine Down syndrome model perturbs hematopoietic progenitor cells in a manner similar to that observed in human Down syndrome by inducing gene expression changes and lineage priming in early multi-potential progenitors. We show that the gene expression signature specifically attributable to trisomy of Erg in the murine model is strongly correlated with gene expression changes in human Down syndrome hematopoietic cells. The data suggest that Erg is an important regulator of megakaryocyte-erythroid lineage specification in multipotential hematopoietic cells and that trisomy of Erg in the context of DS prediposes to a transient myeloproliferative disorder and acute megakaryocyte leukaemia in a multi-step model of leukemogenesis.
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109
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Saleiro D, Mehrotra S, Kroczynska B, Beauchamp EM, Lisowski P, Majchrzak-Kita B, Bhagat TD, Stein BL, McMahon B, Altman JK, Kosciuczuk EM, Baker DP, Jie C, Jafari N, Thompson CB, Levine RL, Fish EN, Verma AK, Platanias LC. Central role of ULK1 in type I interferon signaling. Cell Rep 2015; 11:605-17. [PMID: 25892232 DOI: 10.1016/j.celrep.2015.03.056] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 02/16/2015] [Accepted: 03/25/2015] [Indexed: 11/17/2022] Open
Abstract
We provide evidence that the Unc-51-like kinase 1 (ULK1) is activated during engagement of the type I interferon (IFN) receptor (IFNR). Our studies demonstrate that the function of ULK1 is required for gene transcription mediated via IFN-stimulated response elements (ISRE) and IFNγ activation site (GAS) elements and controls expression of key IFN-stimulated genes (ISGs). We identify ULK1 as an upstream regulator of p38α mitogen-activated protein kinase (MAPK) and establish that the regulatory effects of ULK1 on ISG expression are mediated possibly by engagement of the p38 MAPK pathway. Importantly, we demonstrate that ULK1 is essential for antiproliferative responses and type I IFN-induced antineoplastic effects against malignant erythroid precursors from patients with myeloproliferative neoplasms. Together, these data reveal a role for ULK1 as a key mediator of type I IFNR-generated signals that control gene transcription and induction of antineoplastic responses.
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110
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Chung J, Bauer DE, Ghamari A, Nizzi CP, Deck KM, Kingsley PD, Yien YY, Huston NC, Chen C, Schultz IJ, Dalton AJ, Wittig JG, Palis J, Orkin SH, Lodish HF, Eisenstein RS, Cantor AB, Paw BH. The mTORC1/4E-BP pathway coordinates hemoglobin production with L-leucine availability. Sci Signal 2015; 8:ra34. [PMID: 25872869 PMCID: PMC4402725 DOI: 10.1126/scisignal.aaa5903] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
In multicellular organisms, the mechanisms by which diverse cell types acquire distinct amino acids and how cellular function adapts to their availability are fundamental questions in biology. We found that increased neutral essential amino acid (NEAA) uptake was a critical component of erythropoiesis. As red blood cells matured, expression of the amino acid transporter gene Lat3 increased, which increased NEAA import. Inadequate NEAA uptake by pharmacologic inhibition or RNAi-mediated knockdown of LAT3 triggered a specific reduction in hemoglobin production in zebrafish embryos and murine erythroid cells through the mTORC1 (mammalian target of rapamycin complex 1)/4E-BP (eukaryotic translation initiation factor 4E-binding protein) pathway. CRISPR-mediated deletion of members of the 4E-BP family in murine erythroid cells rendered them resistant to mTORC1 and LAT3 inhibition and restored hemoglobin production. These results identify a developmental role for LAT3 in red blood cells and demonstrate that mTORC1 serves as a homeostatic sensor that couples hemoglobin production at the translational level to sufficient uptake of NEAAs, particularly L-leucine.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Amino Acid Transport Systems, Basic/genetics
- Amino Acid Transport Systems, Basic/metabolism
- Animals
- Animals, Genetically Modified
- CRISPR-Cas Systems
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cell Cycle Proteins
- Cell Line, Tumor
- Cells, Cultured
- Embryo, Mammalian/blood supply
- Embryo, Mammalian/embryology
- Embryo, Mammalian/metabolism
- Embryo, Nonmammalian/embryology
- Embryo, Nonmammalian/metabolism
- Erythroid Cells/metabolism
- Erythropoiesis/genetics
- Eukaryotic Initiation Factors/genetics
- Eukaryotic Initiation Factors/metabolism
- Gene Expression Regulation, Developmental
- HEK293 Cells
- Hemoglobins/genetics
- Hemoglobins/metabolism
- Humans
- Immunoblotting
- Leucine/metabolism
- Mechanistic Target of Rapamycin Complex 1
- Mice
- Microscopy, Confocal
- Multiprotein Complexes/genetics
- Multiprotein Complexes/metabolism
- Phosphoproteins/genetics
- Phosphoproteins/metabolism
- RNA Interference
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction/genetics
- TOR Serine-Threonine Kinases/genetics
- TOR Serine-Threonine Kinases/metabolism
- Zebrafish
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111
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Bianchi N, Finotti A, Ferracin M, Lampronti I, Zuccato C, Breveglieri G, Brognara E, Fabbri E, Borgatti M, Negrini M, Gambari R. Increase of microRNA-210, decrease of raptor gene expression and alteration of mammalian target of rapamycin regulated proteins following mithramycin treatment of human erythroid cells. PLoS One 2015; 10:e0121567. [PMID: 25849663 PMCID: PMC4388523 DOI: 10.1371/journal.pone.0121567] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 02/13/2015] [Indexed: 02/04/2023] Open
Abstract
Expression and regulation of microRNAs is an emerging issue in erythroid differentiation and globin gene expression in hemoglobin disorders. In the first part of this study microarray analysis was performed both in mithramycin-induced K562 cells and erythroid precursors from healthy subjects or β-thalassemia patients producing low or high levels of fetal hemoglobin. We demonstrated that: (a) microRNA-210 expression is higher in erythroid precursors from β-thalassemia patients with high production of fetal hemoglobin; (b) microRNA-210 increases as a consequence of mithramycin treatment of K562 cells and human erythroid progenitors both from healthy and β-thalassemia subjects; (c) this increase is associated with erythroid induction and elevated expression of γ-globin genes; (d) an anti-microRNA against microRNA-210 interferes with the mithramycin-induced changes of gene expression. In the second part of the study we have obtained convergent evidences suggesting raptor mRNA as a putative target of microRNA-210. Indeed, microRNA-210 binding sites of its 3’-UTR region were involved in expression and are targets of microRNA-210-mediated modulation in a luciferase reporter assays. Furthermore, (i) raptor mRNA and protein are down-regulated upon mithramycin-induction both in K562 cells and erythroid progenitors from healthy and β-thalassemia subjects. In addition, (ii) administration of anti-microRNA-210 to K562 cells decreased endogenous microRNA-210 and increased raptor mRNA and protein expression. Finally, (iii) treatment of K562 cells with premicroRNA-210 led to a decrease of raptor mRNA and protein. In conclusion, microRNA-210 and raptor are involved in mithramycin-mediated erythroid differentiation of K562 cells and participate to the fine-tuning and control of γ-globin gene expression in erythroid precursor cells.
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112
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Yang Y, Liu X, Xiao F, Xue S, Xu Q, Yin Y, Sun H, Xu J, Wang H, Zhang Q, Wang H, Wang L. Spred2 modulates the erythroid differentiation induced by imatinib in chronic myeloid leukemia cells. PLoS One 2015; 10:e0117573. [PMID: 25688862 PMCID: PMC4331423 DOI: 10.1371/journal.pone.0117573] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 12/28/2014] [Indexed: 01/02/2023] Open
Abstract
Differentiation induction is currently considered as an alternative strategy for treating chronic myelogenous leukemia (CML). Our previous work has demonstrated that Sprouty-related EVH1 domainprotein2 (Spred2) was involved in imatinib mediated cytotoxicity in CML cells. However, its roles in growth and lineage differentiation of CML cells remain unknown. In this study, we found that CML CD34+ cells expressed lower level of Spred2 compared with normal hematopoietic progenitor cells, and adenovirus mediated restoration of Spred2 promoted the erythroid differentiation of CML cells. Imatinib could induce Spred2 expression and enhance erythroid differentiation in K562 cells. However, the imatinib induced erythroid differentiation could be blocked by Spred2 silence using lentiviral vector PLKO.1-shSpred2. Spred2 interference activated phosphorylated-ERK (p-ERK) and inhibited erythroid differentiation, while ERK inhibitor, PD98059, could restore the erythroid differentiation, suggesting Spred2 regulated the erythroid differentiation partly through ERK signaling. Furthermore, Spred2 interference partly restored p-ERK level leading to inhibition of erythroid differentiation in imatinib treated K562 cells. In conclusion, Spred2 was involved in erythroid differentiation of CML cells and participated in imatinib induced erythroid differentiation partly through ERK signaling.
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113
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Patra M, Mukhopadhyay C, Chakrabarti A. Probing conformational stability and dynamics of erythroid and nonerythroid spectrin: effects of urea and guanidine hydrochloride. PLoS One 2015; 10:e0116991. [PMID: 25617632 PMCID: PMC4305312 DOI: 10.1371/journal.pone.0116991] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 12/18/2014] [Indexed: 11/19/2022] Open
Abstract
We have studied the conformational stability of the two homologous membrane skeletal proteins, the erythroid and non-erythroid spectrins, in their dimeric and tetrameric forms respectively during unfolding in the presence of urea and guanidine hydrochloride (GuHCl). Fluorescence and circular dichroism (CD) spectroscopy have been used to study the changes of intrinsic tryptophan fluorescence, anisotropy, far UV-CD and extrinsic fluorescence of bound 1-anilinonapthalene-8-sulfonic acid (ANS). Chemical unfolding of both proteins were reversible and could be described as a two state transition. The folded erythroid spectrin and non-erythroid spectrin were directly converted to unfolded monomer without formation of any intermediate. Fluorescence quenching, anisotropy, ANS binding and dynamic light scattering data suggest that in presence of low concentrations of the denaturants (up-to 1M) hydrogen bonding network and van der Waals interaction play a role inducing changes in quaternary as well as tertiary structures without complete dissociation of the subunits. This is the first report of two large worm like, multi-domain proteins obeying twofold rule which is commonly found in small globular proteins. The free energy of stabilization (ΔGuH20) for the dimeric spectrin has been 20 kcal/mol lesser than the tetrameric from.
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114
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Ginder GD. Epigenetic regulation of fetal globin gene expression in adult erythroid cells. Transl Res 2015; 165:115-25. [PMID: 24880147 PMCID: PMC4227965 DOI: 10.1016/j.trsl.2014.05.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 05/02/2014] [Accepted: 05/05/2014] [Indexed: 10/25/2022]
Abstract
The developmental regulation of globin gene expression has served as an important model for understanding higher eukaryotic transcriptional control mechanisms. During human erythroid development, there is a sequential switch from expression of the embryonic ε-globin gene to the fetal ɣ-globin gene in utero, and postpartum the ɣ-globin gene is silenced, as the β-globin gene becomes the predominantly expressed locus. Because the expression of normally silenced fetal ɣ-type globin genes and resultant production of fetal hemoglobin (HbF) in adult erythroid cells can ameliorate the pathophysiological consequences of both abnormal β-globin chains in sickle cell anemia and deficient β-globin chain production in β-thalassemia, understanding the complex mechanisms of this developmental switch has direct translational clinical relevance. Of particular interest for translational research are the factors that mediate silencing of the ɣ-globin gene in adult stage erythroid cells. In addition to the regulatory roles of transcription factors and their cognate DNA sequence motifs, there has been a growing appreciation of the role of epigenetic signals and their cognate factors in gene regulation, and in particular in gene silencing through chromatin. Much of the information about epigenetic silencing stems from studies of globin gene regulation. As discussed here, the term epigenetics refers to postsynthetic modifications of DNA and chromosomal histone proteins that affect gene expression and can be inherited through somatic cell replication. A full understanding of the molecular mechanisms of epigenetic silencing of HbF expression should facilitate the development of more effective treatment of β-globin chain hemoglobinopathies.
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115
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Yien YY, Gnanapragasam MN, Gupta R, Rivella S, Bieker JJ. Alternative splicing of EKLF/KLF1 in murine primary erythroid tissues. Exp Hematol 2015; 43:65-70. [PMID: 25283745 PMCID: PMC4268327 DOI: 10.1016/j.exphem.2014.08.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 07/31/2014] [Accepted: 08/16/2014] [Indexed: 11/16/2022]
Abstract
Alternative splicing has emerged as a vital way to expand the functional repertoire of a set number of mammalian genes. For example, such changes can dramatically alter the function and cellular localization of transcription factors. With this in mind, we addressed whether EKLF/KLF1 mRNA, coding for a transcription factor that plays a critical role in erythropoietic gene regulation, is alternatively spliced. We find that EKLF mRNA undergoes exon skipping only in primary tissues and that this splice variant (SV) remains at a very low level in both embryonic and adult erythroid cells, as well as during terminal differentiation. The resultant protein is truncated and partially encodes a non-erythroid Krüppel-like factor amino acid sequence. Its overexpression can alter full-length erythroid Krüppel-like factor function at selected promoters. We discuss these results in the context of stress and with respect to recent global studies on the role of alternative splicing during terminal erythroid differentiation.
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116
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Gushchanskaia ES, Artemov AA, Ul'ianov SV, Penin AA, Logacheva MD, Razin SV, Gavrilov AA. [Spatial organization of house-keeping genes in interphase nuclei]. Mol Biol (Mosk) 2014; 48:1008-1018. [PMID: 25845242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Spatial organization of the eukaryotic genome is tightly connected to its functioning. In particular, the interaction of gene promoters with remote enhancer elements in active chromatin hubs, as well as the recruitment of genes to the common transcription factories plays an important role in regulation of gene transcription. Most of works related to the analysis of spatial interaction of genome regulatory elements relies on models of tissue-specific genes. Meanwhile, it remains unclear to which extent the spatial organization of chromosomes is guided by house-keeping genes that are transcribed in most of cell types and outnumber the transcribed tissue-specific genes. To address this question, we used the 4C technique to characterize genome-wide the spatial contacts of the chicken house-keeping genes CARHSP1 and TRAP1 situated on chromosome 14. The promoters of these genes had an increased frequency of interaction with chromosome regions enriched in CpG islands and binding motifs for the ubiquitous transcription factor Sp1, both of which mark promoters of house-keeping genes, and overall with transcriptionally active regions. By contrast, the analysis of interaction of a gene poor region of chromosome 14 revealed no such preferences. The evidence for the interaction of house-keeping gene promoters were also obtained in independent cytological experiments aimed at visualization of non-methylated CpG islands in individual nuclei of human cells, which showed clustering of CpG islands in the nuclear space. Altogether, the results of our work suggest that the interaction of house-keeping genes constitutes an important factor that determines the spatial organization of interphase chromosomes.
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McIver SC, Kang YA, DeVilbiss AW, O'Driscoll CA, Ouellette JN, Pope NJ, Camprecios G, Chang CJ, Yang D, Bouhassira EE, Ghaffari S, Bresnick EH. The exosome complex establishes a barricade to erythroid maturation. Blood 2014; 124:2285-97. [PMID: 25115889 PMCID: PMC4183988 DOI: 10.1182/blood-2014-04-571083] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 07/25/2014] [Indexed: 12/28/2022] Open
Abstract
Complex genetic networks control hematopoietic stem cell differentiation into progenitors that give rise to billions of erythrocytes daily. Previously, we described a role for the master regulator of erythropoiesis, GATA-1, in inducing genes encoding components of the autophagy machinery. In this context, the Forkhead transcription factor, Foxo3, amplified GATA-1-mediated transcriptional activation. To determine the scope of the GATA-1/Foxo3 cooperativity, and to develop functional insights, we analyzed the GATA-1/Foxo3-dependent transcriptome in erythroid cells. GATA-1/Foxo3 repressed expression of Exosc8, a pivotal component of the exosome complex, which mediates RNA surveillance and epigenetic regulation. Strikingly, downregulating Exosc8, or additional exosome complex components, in primary erythroid precursor cells induced erythroid cell maturation. Our results demonstrate a new mode of controlling erythropoiesis in which multiple components of the exosome complex are endogenous suppressors of the erythroid developmental program.
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Yien YY, Robledo RF, Schultz IJ, Takahashi-Makise N, Gwynn B, Bauer DE, Dass A, Yi G, Li L, Hildick-Smith GJ, Cooney JD, Pierce EL, Mohler K, Dailey TA, Miyata N, Kingsley PD, Garone C, Hattangadi SM, Huang H, Chen W, Keenan EM, Shah DI, Schlaeger TM, DiMauro S, Orkin SH, Cantor AB, Palis J, Koehler CM, Lodish HF, Kaplan J, Ward DM, Dailey HA, Phillips JD, Peters LL, Paw BH. TMEM14C is required for erythroid mitochondrial heme metabolism. J Clin Invest 2014; 124:4294-304. [PMID: 25157825 DOI: 10.1172/jci76979] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/17/2014] [Indexed: 12/15/2022] Open
Abstract
The transport and intracellular trafficking of heme biosynthesis intermediates are crucial for hemoglobin production, which is a critical process in developing red cells. Here, we profiled gene expression in terminally differentiating murine fetal liver-derived erythroid cells to identify regulators of heme metabolism. We determined that TMEM14C, an inner mitochondrial membrane protein that is enriched in vertebrate hematopoietic tissues, is essential for erythropoiesis and heme synthesis in vivo and in cultured erythroid cells. In mice, TMEM14C deficiency resulted in porphyrin accumulation in the fetal liver, erythroid maturation arrest, and embryonic lethality due to profound anemia. Protoporphyrin IX synthesis in TMEM14C-deficient erythroid cells was blocked, leading to an accumulation of porphyrin precursors. The heme synthesis defect in TMEM14C-deficient cells was ameliorated with a protoporphyrin IX analog, indicating that TMEM14C primarily functions in the terminal steps of the heme synthesis pathway. Together, our data demonstrate that TMEM14C facilitates the import of protoporphyrinogen IX into the mitochondrial matrix for heme synthesis and subsequent hemoglobin production. Furthermore, the identification of TMEM14C as a protoporphyrinogen IX importer provides a genetic tool for further exploring erythropoiesis and congenital anemias.
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Trakarnsanga K, Wilson MC, Griffiths RE, Toye AM, Carpenter L, Heesom KJ, Parsons SF, Anstee DJ, Frayne J. Qualitative and quantitative comparison of the proteome of erythroid cells differentiated from human iPSCs and adult erythroid cells by multiplex TMT labelling and nanoLC-MS/MS. PLoS One 2014; 9:e100874. [PMID: 25019302 PMCID: PMC4096399 DOI: 10.1371/journal.pone.0100874] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 05/31/2014] [Indexed: 01/01/2023] Open
Abstract
Induced pluripotent stem cells (iPSC) are an attractive progenitor source for the generation of in vitro blood products. However, before iPSC-derived erythroid cells can be considered for therapeutic use their similarity to adult erythroid cells must be confirmed. We have analysed the proteome of erythroid cells differentiated from the iPSC fibroblast derived line (C19) and showed they express hallmark RBC proteins, including all those of the ankyrin and 4.1R complex. We next compared the proteome of erythroid cells differentiated from three iPSC lines (C19, OCE1, OPM2) with that of adult and cord blood progenitors. Of the 1989 proteins quantified <3% differed in level by 2-fold or more between the different iPSC-derived erythroid cells. When compared to adult cells, 11% of proteins differed in level by 2-fold or more, falling to 1.9% if a 5-fold threshold was imposed to accommodate slight inter-cell line erythropoietic developmental variation. Notably, the level of >30 hallmark erythroid proteins was consistent between the iPSC lines and adult cells. In addition, a sub-population (10-15%) of iPSC erythroid cells in each of the iPSC lines completed enucleation. Aberrant expression of some cytoskeleton proteins may contribute to the failure of the majority of the cells to enucleate since we detected some alterations in cytoskeletal protein abundance. In conclusion, the proteome of erythroid cells differentiated from iPSC lines is very similar to that of normal adult erythroid cells, but further work to improve the induction of erythroid cells in existing iPSC lines or to generate novel erythroid cell lines is required before iPSC-derived red cells can be considered suitable for transfusion therapy.
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Vassen L, Beauchemin H, Lemsaddek W, Krongold J, Trudel M, Möröy T. Growth factor independence 1b (gfi1b) is important for the maturation of erythroid cells and the regulation of embryonic globin expression. PLoS One 2014; 9:e96636. [PMID: 24800817 PMCID: PMC4011847 DOI: 10.1371/journal.pone.0096636] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/09/2014] [Indexed: 12/15/2022] Open
Abstract
Growth factor independence 1b (GFI1B) is a DNA binding repressor of transcription with vital functions in hematopoiesis. Gfi1b-null embryos die at midgestation very likely due to defects in erythro- and megakaryopoiesis. To analyze the full functionality of Gfi1b, we used conditionally deficient mice that harbor floxed Gfi1b alleles and inducible (Mx-Cre, Cre-ERT) or erythroid specific (EpoR-Cre) Cre expressing transgenes. In contrast to the germline knockout, EpoR-Cre mediated erythroid specific ablation of Gfi1b allows full gestation, but causes perinatal lethality with very few mice surviving to adulthood. Both the embryonic deletion of Gfi1b by EpoR-Cre and the deletion in adult mice by Mx-Cre or Cre-ERT leads to reduced numbers of erythroid precursors, perturbed and delayed erythroid maturation, anemia and extramedullary erythropoiesis. Global expression analyses showed that the Hba-x, Hbb-bh1 and Hbb-y embryonic globin genes were upregulated in Gfi1b deficient TER119+ fetal liver cells over the gestation period from day 12.5–17.5 p.c. and an increased level of Hbb-bh1 and Hbb-y embryonic globin gene expression was even maintained in adult Gfi1b deficient mice. While the expression of Bcl11a, a regulator of embryonic globin expression was not affected by Gfi1b deficiency, the expression of Gata1 was reduced and the expression of Sox6, also involved in globin switch, was almost entirely lost when Gfi1b was absent. These findings establish Gfi1b as a regulator of embryonic globin expression and embryonic and adult erythroid maturation.
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Chang KH, Fang X, Wang H, Huang A, Cao H, Yang Y, Bonig H, Stamatoyannopoulos JA, Papayannopoulou T. Epigenetic modifications and chromosome conformations of the beta globin locus throughout development. Stem Cell Rev Rep 2014; 9:397-407. [PMID: 22374078 DOI: 10.1007/s12015-012-9355-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Human embryonic stem cells provide an alternative to using human embryos for studying developmentally regulated gene expression. The co-expression of high levels of embryonic ε and fetal γ globin by the hESC-derived erythroblasts allows the interrogation of ε globin regulation at the transcriptional and epigenetic level which could only be attained previously by studying cell lines or transgenic mice. In this study, we compared the histone modifications across the β globin locus of the undifferentiated hESCs and hESC-, FL-, and mobilized PB CD34(+) cells-derived erythroblasts, which have distinct globin expression patterns corresponding to their developmental stages. We demonstrated that the histone codes employed by the β globin locus are conserved throughout development. Furthermore, in spite of the close proximity of the ε globin promoter, as compared to the β or γ globin promoter, with the LCR, a chromatin loop was also formed between the LCR and the active ε globin promoter, similar to the loop that forms between the β or γ globin promoters and the LCR, in contrary to the previously proposed tracking mechanism.
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Kong XZ, Yin RH, Ning HM, Zheng WW, Dong XM, Yang Y, Xu FF, Li JJ, Zhan YQ, Yu M, Ge CH, Zhang JH, Chen H, Li CY, Yang XM. Effects of THAP11 on erythroid differentiation and megakaryocytic differentiation of K562 cells. PLoS One 2014; 9:e91557. [PMID: 24637716 PMCID: PMC3956667 DOI: 10.1371/journal.pone.0091557] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 02/13/2014] [Indexed: 12/16/2022] Open
Abstract
Hematopoiesis is a complex process regulated by sets of transcription factors in a stage-specific and context-dependent manner. THAP11 is a transcription factor involved in cell growth, ES cell pluripotency, and embryogenesis. Here we showed that THAP11 was down-regulated during erythroid differentiation but up-regulated during megakaryocytic differentiation of cord blood CD34+ cells. Overexpression of THAP11 in K562 cells inhibited the erythroid differentiation induced by hemin with decreased numbers of benzidine-positive cells and decreased mRNA levels of α-globin (HBA) and glycophorin A (GPA), and knockdown of THAP11 enhanced the erythroid differentiation. Conversely, THAP11 overexpression accelerated the megakaryocytic differentiation induced by phorbol myristate acetate (PMA) with increased percentage of CD41+ cells, increased numbers of 4N cells, and elevated CD61 mRNA levels, and THAP11 knockdown attenuated the megakaryocytic differentiation. The expression levels of transcription factors such as c-Myc, c-Myb, GATA-2, and Fli1 were changed by THAP11 overexpression. In this way, our results suggested that THAP11 reversibly regulated erythroid and megakaryocytic differentiation.
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Stadhouders R, Aktuna S, Thongjuea S, Aghajanirefah A, Pourfarzad F, van Ijcken W, Lenhard B, Rooks H, Best S, Menzel S, Grosveld F, Thein SL, Soler E. HBS1L-MYB intergenic variants modulate fetal hemoglobin via long-range MYB enhancers. J Clin Invest 2014; 124:1699-710. [PMID: 24614105 DOI: 10.1172/jci71520] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 01/09/2014] [Indexed: 01/21/2023] Open
Abstract
Genetic studies have identified common variants within the intergenic region (HBS1L-MYB) between GTP-binding elongation factor HBS1L and myeloblastosis oncogene MYB on chromosome 6q that are associated with elevated fetal hemoglobin (HbF) levels and alterations of other clinically important human erythroid traits. It is unclear how these noncoding sequence variants affect multiple erythrocyte characteristics. Here, we determined that several HBS1L-MYB intergenic variants affect regulatory elements that are occupied by key erythroid transcription factors within this region. These elements interact with MYB, a critical regulator of erythroid development and HbF levels. We found that several HBS1L-MYB intergenic variants reduce transcription factor binding, affecting long-range interactions with MYB and MYB expression levels. These data provide a functional explanation for the genetic association of HBS1L-MYB intergenic polymorphisms with human erythroid traits and HbF levels. Our results further designate MYB as a target for therapeutic induction of HbF to ameliorate sickle cell and β-thalassemia disease severity.
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Li Y, Bai H, Zhang Z, li W, Dong L, Wei X, Ma Y, Zhang J, Yu J, Sun G, Wang F. The up-regulation of miR-199b-5p in erythroid differentiation is associated with GATA-1 and NF-E2. Mol Cells 2014; 37:213-9. [PMID: 24608802 PMCID: PMC3969041 DOI: 10.14348/molcells.2014.2288] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 12/28/2013] [Accepted: 12/30/2013] [Indexed: 11/27/2022] Open
Abstract
MicroRNAs (miRNAs) represent a class of small non-coding regulatory RNAs that play important roles in normal hematopoiesis, including erythropoiesis. Although studies have identified several miRNAs that regulate erythroid commitment and differentiation, we do not understand the mechanism by which the crucial erythroid transcription factors, GATA-1and NF-E2 directly regulate and control differentiation via miRNA pathways. In this study, we identified miR-199b-5p as a key regulator of human erythropoiesis, and its expression was up-regulated during the erythroid differentiation of K562 cells. Furthermore, the increase of miR-199b-5p in erythroid cells occurred in a GATA-1- and NF-E2-dependent manner during erythrocyte maturation. Both GATA-1 and NF-E2 bound upstream of the miR-199b gene locus and activated its transcription. Forced expression of miRNA-199b-5p in K562 cells affected erythroid cell proliferation and maturation. Moreover, we identified c-Kit as a direct target of miR-199b-5p in erythroid cells. Taken together, our results establish a functional link among the erythroid transcription factors GATA-1/NF-E2, miR-199b-5p and c-Kit, and provide new insights into the coupling of transcription and post-transcription regulation in erythroid differentiation.
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Madzo J, Liu H, Rodriguez A, Vasanthakumar A, Sundaravel S, Caces DBD, Looney TJ, Zhang L, Lepore JB, Macrae T, Duszynski R, Shih AH, Song CX, Yu M, Yu Y, Grossman R, Raumann B, Verma A, He C, Levine RL, Lavelle D, Lahn BT, Wickrema A, Godley LA. Hydroxymethylation at gene regulatory regions directs stem/early progenitor cell commitment during erythropoiesis. Cell Rep 2013; 6:231-244. [PMID: 24373966 DOI: 10.1016/j.celrep.2013.11.044] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 08/21/2013] [Accepted: 11/26/2013] [Indexed: 01/28/2023] Open
Abstract
Hematopoietic stem cell differentiation involves the silencing of self-renewal genes and induction of a specific transcriptional program. Identification of multiple covalent cytosine modifications raises the question of how these derivatized bases influence stem cell commitment. Using a replicative primary human hematopoietic stem/progenitor cell differentiation system, we demonstrate dynamic changes of 5-hydroxymethylcytosine (5-hmC) during stem cell commitment and differentiation to the erythroid lineage. Genomic loci that maintain or gain 5-hmC density throughout erythroid differentiation contain binding sites for erythroid transcription factors and several factors not previously recognized as erythroid-specific factors. The functional importance of 5-hmC was demonstrated by impaired erythroid differentiation, with augmentation of myeloid potential, and disrupted 5-hmC patterning in leukemia patient-derived CD34+ stem/early progenitor cells with TET methylcytosine dioxygenase 2 (TET2) mutations. Thus, chemical conjugation and affinity purification of 5-hmC-enriched sequences followed by sequencing serve as resources for deciphering functional implications for gene expression during stem cell commitment and differentiation along a particular lineage.
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